Radical-SAM dependent nucleotide dehydratase (SAND), rectification of the names of an ancient iron-sulfur enzyme using NC-IUBMB recommendations.
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ABSTRACT:
SUBMITTER: Ji Y
PROVIDER: S-EPMC9642334 | biostudies-literature | 2022
REPOSITORIES: biostudies-literature
Publications
Radical-SAM dependent nucleotide dehydratase (SAND), rectification of the names of an ancient iron-sulfur enzyme using NC-IUBMB recommendations.
Ji Yuxuan Y Wei Li L Da Anqi A Stark Holger H Hagedoorn Peter-Leon PL Ciofi-Baffoni Simone S Cowley Sally A SA Louro Ricardo O RO Todorovic Smilja S Mroginski Maria Andrea MA Nicolet Yvain Y Roessler Maxie M MM Le Brun Nick E NE Piccioli Mario M James William S WS Hagen Wilfred R WR Ebrahimi Kourosh H KH
Frontiers in molecular biosciences 20221021
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Project description:TYW1 is a radical S-adenosyl-l-methionine (SAM) enzyme that catalyzes the condensation of pyruvate and N-methylguanosine-containing tRNAPhe, forming 4-demethylwyosine-containing tRNAPhe. Homologues of TYW1 are found in both archaea and eukarya; archaeal homologues consist of a single domain, while eukaryal homologues contain a flavin binding domain in addition to the radical SAM domain shared with archaeal homologues. In this study, TYW1 from Saccharomyces cerevisiae (ScTYW1) was heterologously expressed in Escherichia coli and purified to homogeneity. ScTYW1 is purified with 0.54 ± 0.07 and 4.2 ± 1.9 equiv of flavin mononucleotide (FMN) and iron, respectively, per mole of protein, suggesting the protein is ∼50% replete with Fe-S clusters and FMN. While both NADPH and NADH are sufficient for activity, significantly more product is observed when used in combination with flavin nucleotides. ScTYW1 is the first example of a radical SAM flavoenzyme that is active with NAD(P)H alone.
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